RATIONALE: Radiation therapy uses high-energy x-rays to damage tumor cells. It is not yet known whether giving radiation therapy during surgery is more effective than standard radiation therapy in treating brain metastases.

PURPOSE: Randomized phase III trial to compare the effectiveness of radiation therapy with or without radiosurgery in treating patients with brain metastases that cannot be removed during surgery.

OBJECTIVES: I. Compare the overall survival of patients with one unresected brain metastasis treated with conventional whole brain radiotherapy (WBRT) with vs. without a stereotactic radiosurgery (SRS) boost. II. Compare sites of recurrence and cause of death in these patients treated with WBRT followed by SRS vs. WBRT alone.

OUTLINE: This is a randomized, multicenter study. Patients are stratified according to center and extracranial disease (yes or no). Patients are randomized to one of two treatment arms. Arm I: Patients receive fractionated external beam whole brain irradiation (WBRT) 5 days each week for 3 weeks. Both portals are treated during each radiotherapy session. Patients who still have a solitary lesion with a diameter no greater than 4.0 cm also receive stereotactic radiosurgery within 7 days of completing WBRT. Arm II: Patients receive WBRT only. Patients are followed every 3 months for 1 year, then every 4 months for 2 years, and then annually.

PROJECTED ACCRUAL: A total of 262 patients will be accrued over 2.5-3.75 years for this study. The study may close early if interim analysis after 33% and 67% of patients have been followed for 6 months produces significant results. After 6/14/99 an additional 46 patients with a solitary brain metastasis only will be accrued.

DISEASE CHARACTERISTICS: No more than 1 unresected or subtotally resected brain metastasis lesion from histologically confirmed systemic malignancy Eligible only if surgical resection refused by patient or resection deemed inappropriate by patient's physician 1 intraparenchymal metastasis clearly defined on contrast enhanced MRI Maximum diameter of lesion no greater than 4.0 cm No leukemia or lymphoma Extracranial sites of primary metastatic disease allowed if no clinical or radiographic evidence of progression within 1 month prior to entry No metastasis to brainstem, midbrain, pons, or medulla No leptomeningeal metastasis by MRI or CSF evaluation No metastasis within 10 mm of optic nerves and chiasm (area must be excluded from high dose stereotactic radiosurgery boost field)

PATIENT CHARACTERISTICS: Age: 18 and over Performance status: 70-100% Karnofsky Hematopoietic: Absolute neutrophil count at least 1,000/mm3 Platelet count at least 50,000/mm3 Hemoglobin at least 8 g/dL Hepatic: Not specified Renal: Not specified Other: Neurologic status 0-2 No major medical or psychiatric contraindication to protocol entry Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY: Biologic therapy: Not specified Chemotherapy: No concurrent chemotherapy for systemic cancer Endocrine therapy: Concurrent hormonal therapy, including tamoxifen, allowed Radiotherapy: No prior cranial radiotherapy Surgery: Prior subtotal resection allowed Other: No other concurrent treatment for brain metastasis until recurrence